The medical sector is characterized by a wide range of machines with different characteristics and degrees of complexity, which are used in heterogeneous functions, to monitoring and prevention to treatment of diseases. The high technological content and reliability of this equipment make a decisive contribution to improving the health and therefore quality of life. The isolation transformers to medical hospital use require a particular construction and isolation system that allows a safe and functional use. Emiltrafo transformers are designed and manufactured in accordance with CEI EN 61558-2-15 and DIN EN 60601-1 3rd ed. The latter requires for instance that each transformer is designed and built ensuring a very low leakage current (<50mA) and a very high efficiency.